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塑料的挤出速度或塑化的好坏与使用的塑料材质和温度控制有关，各种塑料的塑化温度有所不同。如果要快速挤出塑料，只有材质优良，温度适当，才能实现。另外，挤出速度与挤出厚度也有密切关系，正常挤出过程中，出胶量大，挤出速度慢；反之，挤出速度就快，在保证质量的前提下，可适当提高挤出速度。三、 牵引速度挤包制品是由牵引装置拖动通过机头的，为保证产品的质量，要求牵引速度均匀稳定，与螺杆转速协调，以保证挤出厚度和制品外径的均匀性。如果牵引速度不稳定，挤包层易形成竹节状，而牵引过慢时挤出厚度大，且发生堆胶或空管现象；牵引速度过快时，易造成挤出拉薄拉细，甚至出现脱胶漏包现象。所以正常挤出过程中，一定要控制好牵引速度。四、 冷塑料挤制工艺制度中的冷却也是很重要的一项。一般分成螺杆冷却、机身冷却，以及产品的冷却。1. 螺杆的冷却螺杆冷却的作用是消除摩擦过热，稳定挤出压力，促使塑料搅拌均匀，提高塑化质量。但其使用必须适当，尤其不能过甚，否则机筒内塑料熔体骤然冷却，会导致严重事故的发生。而螺杆冷却在挤出前是绝对禁止使用的，否则也会酿成严重的设备事故。
2. 机身的冷却机身冷却的作用是增加机筒散热，以此克服摩擦过热形成的升温，因为这一温升在挤出过程中，甚至在切断加热电源后也不能停止，从而使合理的温度不能得以长期维持，必须增加散热，而使机筒冷却下来，以维持挤出过程中的热平衡。机身冷却是分段进行的，主要以风机冷却为主，考虑到机身各段的功能不同，对均化段冷却的使用尤其注意3. 产品的冷却产品冷却是确保制品几何形状和内部结构的重要措施。塑料挤包层在离开机头后，应立即进行冷却，否则会在重力作用下发生变形。对于聚氯乙稀等非结晶材料可以不考虑结晶的问题，塑料制品可采用急冷方法，用水直接冷却，使其在冷却水槽中冷透，不再变形。而聚乙烯，聚丙烯等结晶型聚合物的冷却，则应考虑到结晶问题，如果采用急冷方法，会给塑料制品组织带来不利的影响，产生内应力，这是导致产品日后产生龟裂的原因之一，必须在挤塑工艺中予以重视；聚乙烯、聚丙烯等结晶型塑料的挤包层宜用逐步降温的温水冷却方法来进行，一般视设备辅机设施而定，冷却水槽应分段分节，水温可由塑料挤包层进入第一段水槽的75℃～85℃温度开始，逐段降低水温，直至室温，各段水温的温差越小越合理。五、 挤出工艺的技术要求
By the extruder material handling and homogenization analysis of viscous fluid flow rate, the plastic flow rate (the extrusion speed) and the screw speed is proportional to, due to the convenient adjustment, screw extrusion process characterization of extrusion speed speed is an important action variables. Therefore, in normal circumstances, is a modern extruder screw speed to enhance productive capacity, an important means to realize high speed extrusion. But to the length of the plastic melt analysis, increase screw speed, on the one hand because of the enhanced shear so that viscous dissipation heat increases on the other, in the case of no head pressure control, screw speed, increase, increase flow rate, shortening travel time within the material in the machine. And the effects of the latter exceeds the former, will melt to extend the length of the segment and disrupt the normal process of extrusion. So when you need to increase the screw speed to increase the extrusion speed, temperature or control head pressure must be increased in order to achieve their goals. Plastic extrusion speed or plasticized quality associated with use of plastic materials and temperature control, all kinds of plastic the plasticizing temperature is different. If you want to quickly extrude plastic, only fine materials, temperature can be achieved. In addition, the extrusion speed of extrusion thickness also have close relations, normal in the extrusion process, and the plastic output is large, extrusion speed; instead, squeeze out so quickly, in the premise of guaranteeing quality, it may be appropriate to increase the extrusion speed. Three, the traction speed is dragged by the traction device for extruded products through the nose, in order to ensure product quality, required speed stable, coordinated with the screw speed to ensure that extrusion thickness and homogeneity of the products od. If the speed is not stable, form of bamboo-shaped extruded layer, slow traction when extrusion thickness and stacking or an empty tube; traction when the speed is too fast, easily pull out of thin fine and even degumming leakage phenomenon. So normal in the extrusion process, be sure to control the speed. Four, cold plastic extrusion process cooling is also a very important item in the system. Generally divided into fuselage screw cooling, cooling and cooling of products. 1. screw screw cooling cooling function is to eliminate friction and overheating, stable extrusion pressure, plastic mixing and improve the quality of plastic. But its use must be appropriate and, in particular, has been, or sudden cooling cylinder plastic melt, can lead to serious accidents occurred. Screw cooling in front of the extrusion is an absolute prohibition of the use, otherwise it will lead to serious accidents. 2. the cooling effect is cooling of the fuselage the fuselage to increase barrel cooling, to overcome the friction heat forming temperature, because the temperature rise in the extrusion process, even after power off does not stop, so that the temperature can not be reasonably sustained, must increase the heat dissipation and cooling down the barrel to maintain thermal equilibrium in the extrusion process. Body cooling segment, mainly cooling fan-oriented, taking into account the function in the body paragraphs, use of homogenizing and cooling with particular attention to 3. Cooling products cooling is used to ensure that the products of the product geometry and internal structure of important measures. Plastic extruded layers in after leaving the die, it should be cooled immediately, otherwise it will deform under the action of gravity. For non-crystalline materials such as polyvinyl chloride crystallization problems can be ignored, plastic ...
